1 #include <linux/capability.h> 2 #include <linux/blkdev.h> 3 #include <linux/export.h> 4 #include <linux/gfp.h> 5 #include <linux/blkpg.h> 6 #include <linux/hdreg.h> 7 #include <linux/backing-dev.h> 8 #include <linux/fs.h> 9 #include <linux/blktrace_api.h> 10 #include <linux/pr.h> 11 #include <linux/uaccess.h> 12 13 static int blkpg_ioctl(struct block_device *bdev, struct blkpg_ioctl_arg __user *arg) 14 { 15 struct block_device *bdevp; 16 struct gendisk *disk; 17 struct hd_struct *part, *lpart; 18 struct blkpg_ioctl_arg a; 19 struct blkpg_partition p; 20 struct disk_part_iter piter; 21 long long start, length; 22 int partno; 23 24 if (!capable(CAP_SYS_ADMIN)) 25 return -EACCES; 26 if (copy_from_user(&a, arg, sizeof(struct blkpg_ioctl_arg))) 27 return -EFAULT; 28 if (copy_from_user(&p, a.data, sizeof(struct blkpg_partition))) 29 return -EFAULT; 30 disk = bdev->bd_disk; 31 if (bdev != bdev->bd_contains) 32 return -EINVAL; 33 partno = p.pno; 34 if (partno <= 0) 35 return -EINVAL; 36 switch (a.op) { 37 case BLKPG_ADD_PARTITION: 38 start = p.start >> 9; 39 length = p.length >> 9; 40 /* check for fit in a hd_struct */ 41 if (sizeof(sector_t) == sizeof(long) && 42 sizeof(long long) > sizeof(long)) { 43 long pstart = start, plength = length; 44 if (pstart != start || plength != length 45 || pstart < 0 || plength < 0 || partno > 65535) 46 return -EINVAL; 47 } 48 /* check if partition is aligned to blocksize */ 49 if (p.start & (bdev_logical_block_size(bdev) - 1)) 50 return -EINVAL; 51 52 mutex_lock(&bdev->bd_mutex); 53 54 /* overlap? */ 55 disk_part_iter_init(&piter, disk, 56 DISK_PITER_INCL_EMPTY); 57 while ((part = disk_part_iter_next(&piter))) { 58 if (!(start + length <= part->start_sect || 59 start >= part->start_sect + part->nr_sects)) { 60 disk_part_iter_exit(&piter); 61 mutex_unlock(&bdev->bd_mutex); 62 return -EBUSY; 63 } 64 } 65 disk_part_iter_exit(&piter); 66 67 /* all seems OK */ 68 part = add_partition(disk, partno, start, length, 69 ADDPART_FLAG_NONE, NULL); 70 mutex_unlock(&bdev->bd_mutex); 71 return PTR_ERR_OR_ZERO(part); 72 case BLKPG_DEL_PARTITION: 73 part = disk_get_part(disk, partno); 74 if (!part) 75 return -ENXIO; 76 77 bdevp = bdget(part_devt(part)); 78 disk_put_part(part); 79 if (!bdevp) 80 return -ENOMEM; 81 82 mutex_lock(&bdevp->bd_mutex); 83 if (bdevp->bd_openers) { 84 mutex_unlock(&bdevp->bd_mutex); 85 bdput(bdevp); 86 return -EBUSY; 87 } 88 /* all seems OK */ 89 fsync_bdev(bdevp); 90 invalidate_bdev(bdevp); 91 92 mutex_lock_nested(&bdev->bd_mutex, 1); 93 delete_partition(disk, partno); 94 mutex_unlock(&bdev->bd_mutex); 95 mutex_unlock(&bdevp->bd_mutex); 96 bdput(bdevp); 97 98 return 0; 99 case BLKPG_RESIZE_PARTITION: 100 start = p.start >> 9; 101 /* new length of partition in bytes */ 102 length = p.length >> 9; 103 /* check for fit in a hd_struct */ 104 if (sizeof(sector_t) == sizeof(long) && 105 sizeof(long long) > sizeof(long)) { 106 long pstart = start, plength = length; 107 if (pstart != start || plength != length 108 || pstart < 0 || plength < 0) 109 return -EINVAL; 110 } 111 part = disk_get_part(disk, partno); 112 if (!part) 113 return -ENXIO; 114 bdevp = bdget(part_devt(part)); 115 if (!bdevp) { 116 disk_put_part(part); 117 return -ENOMEM; 118 } 119 mutex_lock(&bdevp->bd_mutex); 120 mutex_lock_nested(&bdev->bd_mutex, 1); 121 if (start != part->start_sect) { 122 mutex_unlock(&bdevp->bd_mutex); 123 mutex_unlock(&bdev->bd_mutex); 124 bdput(bdevp); 125 disk_put_part(part); 126 return -EINVAL; 127 } 128 /* overlap? */ 129 disk_part_iter_init(&piter, disk, 130 DISK_PITER_INCL_EMPTY); 131 while ((lpart = disk_part_iter_next(&piter))) { 132 if (lpart->partno != partno && 133 !(start + length <= lpart->start_sect || 134 start >= lpart->start_sect + lpart->nr_sects) 135 ) { 136 disk_part_iter_exit(&piter); 137 mutex_unlock(&bdevp->bd_mutex); 138 mutex_unlock(&bdev->bd_mutex); 139 bdput(bdevp); 140 disk_put_part(part); 141 return -EBUSY; 142 } 143 } 144 disk_part_iter_exit(&piter); 145 part_nr_sects_write(part, (sector_t)length); 146 i_size_write(bdevp->bd_inode, p.length); 147 mutex_unlock(&bdevp->bd_mutex); 148 mutex_unlock(&bdev->bd_mutex); 149 bdput(bdevp); 150 disk_put_part(part); 151 return 0; 152 default: 153 return -EINVAL; 154 } 155 } 156 157 /* 158 * This is an exported API for the block driver, and will not 159 * acquire bd_mutex. This API should be used in case that 160 * caller has held bd_mutex already. 161 */ 162 int __blkdev_reread_part(struct block_device *bdev) 163 { 164 struct gendisk *disk = bdev->bd_disk; 165 166 if (!disk_part_scan_enabled(disk) || bdev != bdev->bd_contains) 167 return -EINVAL; 168 if (!capable(CAP_SYS_ADMIN)) 169 return -EACCES; 170 171 lockdep_assert_held(&bdev->bd_mutex); 172 173 return rescan_partitions(disk, bdev); 174 } 175 EXPORT_SYMBOL(__blkdev_reread_part); 176 177 /* 178 * This is an exported API for the block driver, and will 179 * try to acquire bd_mutex. If bd_mutex has been held already 180 * in current context, please call __blkdev_reread_part(). 181 * 182 * Make sure the held locks in current context aren't required 183 * in open()/close() handler and I/O path for avoiding ABBA deadlock: 184 * - bd_mutex is held before calling block driver's open/close 185 * handler 186 * - reading partition table may submit I/O to the block device 187 */ 188 int blkdev_reread_part(struct block_device *bdev) 189 { 190 int res; 191 192 mutex_lock(&bdev->bd_mutex); 193 res = __blkdev_reread_part(bdev); 194 mutex_unlock(&bdev->bd_mutex); 195 196 return res; 197 } 198 EXPORT_SYMBOL(blkdev_reread_part); 199 200 static int blk_ioctl_discard(struct block_device *bdev, fmode_t mode, 201 unsigned long arg, unsigned long flags) 202 { 203 uint64_t range[2]; 204 uint64_t start, len; 205 206 if (!(mode & FMODE_WRITE)) 207 return -EBADF; 208 209 if (copy_from_user(range, (void __user *)arg, sizeof(range))) 210 return -EFAULT; 211 212 start = range[0]; 213 len = range[1]; 214 215 if (start & 511) 216 return -EINVAL; 217 if (len & 511) 218 return -EINVAL; 219 start >>= 9; 220 len >>= 9; 221 222 if (start + len > (i_size_read(bdev->bd_inode) >> 9)) 223 return -EINVAL; 224 return blkdev_issue_discard(bdev, start, len, GFP_KERNEL, flags); 225 } 226 227 static int blk_ioctl_zeroout(struct block_device *bdev, fmode_t mode, 228 unsigned long arg) 229 { 230 uint64_t range[2]; 231 struct address_space *mapping; 232 uint64_t start, end, len; 233 234 if (!(mode & FMODE_WRITE)) 235 return -EBADF; 236 237 if (copy_from_user(range, (void __user *)arg, sizeof(range))) 238 return -EFAULT; 239 240 start = range[0]; 241 len = range[1]; 242 end = start + len - 1; 243 244 if (start & 511) 245 return -EINVAL; 246 if (len & 511) 247 return -EINVAL; 248 if (end >= (uint64_t)i_size_read(bdev->bd_inode)) 249 return -EINVAL; 250 if (end < start) 251 return -EINVAL; 252 253 /* Invalidate the page cache, including dirty pages */ 254 mapping = bdev->bd_inode->i_mapping; 255 truncate_inode_pages_range(mapping, start, end); 256 257 return blkdev_issue_zeroout(bdev, start >> 9, len >> 9, GFP_KERNEL, 258 BLKDEV_ZERO_NOUNMAP); 259 } 260 261 static int put_ushort(unsigned long arg, unsigned short val) 262 { 263 return put_user(val, (unsigned short __user *)arg); 264 } 265 266 static int put_int(unsigned long arg, int val) 267 { 268 return put_user(val, (int __user *)arg); 269 } 270 271 static int put_uint(unsigned long arg, unsigned int val) 272 { 273 return put_user(val, (unsigned int __user *)arg); 274 } 275 276 static int put_long(unsigned long arg, long val) 277 { 278 return put_user(val, (long __user *)arg); 279 } 280 281 static int put_ulong(unsigned long arg, unsigned long val) 282 { 283 return put_user(val, (unsigned long __user *)arg); 284 } 285 286 static int put_u64(unsigned long arg, u64 val) 287 { 288 return put_user(val, (u64 __user *)arg); 289 } 290 291 int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode, 292 unsigned cmd, unsigned long arg) 293 { 294 struct gendisk *disk = bdev->bd_disk; 295 296 if (disk->fops->ioctl) 297 return disk->fops->ioctl(bdev, mode, cmd, arg); 298 299 return -ENOTTY; 300 } 301 /* 302 * For the record: _GPL here is only because somebody decided to slap it 303 * on the previous export. Sheer idiocy, since it wasn't copyrightable 304 * at all and could be open-coded without any exports by anybody who cares. 305 */ 306 EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl); 307 308 static int blkdev_pr_register(struct block_device *bdev, 309 struct pr_registration __user *arg) 310 { 311 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 312 struct pr_registration reg; 313 314 if (!capable(CAP_SYS_ADMIN)) 315 return -EPERM; 316 if (!ops || !ops->pr_register) 317 return -EOPNOTSUPP; 318 if (copy_from_user(®, arg, sizeof(reg))) 319 return -EFAULT; 320 321 if (reg.flags & ~PR_FL_IGNORE_KEY) 322 return -EOPNOTSUPP; 323 return ops->pr_register(bdev, reg.old_key, reg.new_key, reg.flags); 324 } 325 326 static int blkdev_pr_reserve(struct block_device *bdev, 327 struct pr_reservation __user *arg) 328 { 329 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 330 struct pr_reservation rsv; 331 332 if (!capable(CAP_SYS_ADMIN)) 333 return -EPERM; 334 if (!ops || !ops->pr_reserve) 335 return -EOPNOTSUPP; 336 if (copy_from_user(&rsv, arg, sizeof(rsv))) 337 return -EFAULT; 338 339 if (rsv.flags & ~PR_FL_IGNORE_KEY) 340 return -EOPNOTSUPP; 341 return ops->pr_reserve(bdev, rsv.key, rsv.type, rsv.flags); 342 } 343 344 static int blkdev_pr_release(struct block_device *bdev, 345 struct pr_reservation __user *arg) 346 { 347 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 348 struct pr_reservation rsv; 349 350 if (!capable(CAP_SYS_ADMIN)) 351 return -EPERM; 352 if (!ops || !ops->pr_release) 353 return -EOPNOTSUPP; 354 if (copy_from_user(&rsv, arg, sizeof(rsv))) 355 return -EFAULT; 356 357 if (rsv.flags) 358 return -EOPNOTSUPP; 359 return ops->pr_release(bdev, rsv.key, rsv.type); 360 } 361 362 static int blkdev_pr_preempt(struct block_device *bdev, 363 struct pr_preempt __user *arg, bool abort) 364 { 365 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 366 struct pr_preempt p; 367 368 if (!capable(CAP_SYS_ADMIN)) 369 return -EPERM; 370 if (!ops || !ops->pr_preempt) 371 return -EOPNOTSUPP; 372 if (copy_from_user(&p, arg, sizeof(p))) 373 return -EFAULT; 374 375 if (p.flags) 376 return -EOPNOTSUPP; 377 return ops->pr_preempt(bdev, p.old_key, p.new_key, p.type, abort); 378 } 379 380 static int blkdev_pr_clear(struct block_device *bdev, 381 struct pr_clear __user *arg) 382 { 383 const struct pr_ops *ops = bdev->bd_disk->fops->pr_ops; 384 struct pr_clear c; 385 386 if (!capable(CAP_SYS_ADMIN)) 387 return -EPERM; 388 if (!ops || !ops->pr_clear) 389 return -EOPNOTSUPP; 390 if (copy_from_user(&c, arg, sizeof(c))) 391 return -EFAULT; 392 393 if (c.flags) 394 return -EOPNOTSUPP; 395 return ops->pr_clear(bdev, c.key); 396 } 397 398 /* 399 * Is it an unrecognized ioctl? The correct returns are either 400 * ENOTTY (final) or ENOIOCTLCMD ("I don't know this one, try a 401 * fallback"). ENOIOCTLCMD gets turned into ENOTTY by the ioctl 402 * code before returning. 403 * 404 * Confused drivers sometimes return EINVAL, which is wrong. It 405 * means "I understood the ioctl command, but the parameters to 406 * it were wrong". 407 * 408 * We should aim to just fix the broken drivers, the EINVAL case 409 * should go away. 410 */ 411 static inline int is_unrecognized_ioctl(int ret) 412 { 413 return ret == -EINVAL || 414 ret == -ENOTTY || 415 ret == -ENOIOCTLCMD; 416 } 417 418 static int blkdev_flushbuf(struct block_device *bdev, fmode_t mode, 419 unsigned cmd, unsigned long arg) 420 { 421 int ret; 422 423 if (!capable(CAP_SYS_ADMIN)) 424 return -EACCES; 425 426 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 427 if (!is_unrecognized_ioctl(ret)) 428 return ret; 429 430 fsync_bdev(bdev); 431 invalidate_bdev(bdev); 432 return 0; 433 } 434 435 static int blkdev_roset(struct block_device *bdev, fmode_t mode, 436 unsigned cmd, unsigned long arg) 437 { 438 int ret, n; 439 440 ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg); 441 if (!is_unrecognized_ioctl(ret)) 442 return ret; 443 if (!capable(CAP_SYS_ADMIN)) 444 return -EACCES; 445 if (get_user(n, (int __user *)arg)) 446 return -EFAULT; 447 set_device_ro(bdev, n); 448 return 0; 449 } 450 451 static int blkdev_getgeo(struct block_device *bdev, 452 struct hd_geometry __user *argp) 453 { 454 struct gendisk *disk = bdev->bd_disk; 455 struct hd_geometry geo; 456 int ret; 457 458 if (!argp) 459 return -EINVAL; 460 if (!disk->fops->getgeo) 461 return -ENOTTY; 462 463 /* 464 * We need to set the startsect first, the driver may 465 * want to override it. 466 */ 467 memset(&geo, 0, sizeof(geo)); 468 geo.start = get_start_sect(bdev); 469 ret = disk->fops->getgeo(bdev, &geo); 470 if (ret) 471 return ret; 472 if (copy_to_user(argp, &geo, sizeof(geo))) 473 return -EFAULT; 474 return 0; 475 } 476 477 /* set the logical block size */ 478 static int blkdev_bszset(struct block_device *bdev, fmode_t mode, 479 int __user *argp) 480 { 481 int ret, n; 482 483 if (!capable(CAP_SYS_ADMIN)) 484 return -EACCES; 485 if (!argp) 486 return -EINVAL; 487 if (get_user(n, argp)) 488 return -EFAULT; 489 490 if (!(mode & FMODE_EXCL)) { 491 bdgrab(bdev); 492 if (blkdev_get(bdev, mode | FMODE_EXCL, &bdev) < 0) 493 return -EBUSY; 494 } 495 496 ret = set_blocksize(bdev, n); 497 if (!(mode & FMODE_EXCL)) 498 blkdev_put(bdev, mode | FMODE_EXCL); 499 return ret; 500 } 501 502 /* 503 * always keep this in sync with compat_blkdev_ioctl() 504 */ 505 int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd, 506 unsigned long arg) 507 { 508 void __user *argp = (void __user *)arg; 509 loff_t size; 510 unsigned int max_sectors; 511 512 switch (cmd) { 513 case BLKFLSBUF: 514 return blkdev_flushbuf(bdev, mode, cmd, arg); 515 case BLKROSET: 516 return blkdev_roset(bdev, mode, cmd, arg); 517 case BLKDISCARD: 518 return blk_ioctl_discard(bdev, mode, arg, 0); 519 case BLKSECDISCARD: 520 return blk_ioctl_discard(bdev, mode, arg, 521 BLKDEV_DISCARD_SECURE); 522 case BLKZEROOUT: 523 return blk_ioctl_zeroout(bdev, mode, arg); 524 case BLKREPORTZONE: 525 return blkdev_report_zones_ioctl(bdev, mode, cmd, arg); 526 case BLKRESETZONE: 527 return blkdev_reset_zones_ioctl(bdev, mode, cmd, arg); 528 case HDIO_GETGEO: 529 return blkdev_getgeo(bdev, argp); 530 case BLKRAGET: 531 case BLKFRAGET: 532 if (!arg) 533 return -EINVAL; 534 return put_long(arg, (bdev->bd_bdi->ra_pages*PAGE_SIZE) / 512); 535 case BLKROGET: 536 return put_int(arg, bdev_read_only(bdev) != 0); 537 case BLKBSZGET: /* get block device soft block size (cf. BLKSSZGET) */ 538 return put_int(arg, block_size(bdev)); 539 case BLKSSZGET: /* get block device logical block size */ 540 return put_int(arg, bdev_logical_block_size(bdev)); 541 case BLKPBSZGET: /* get block device physical block size */ 542 return put_uint(arg, bdev_physical_block_size(bdev)); 543 case BLKIOMIN: 544 return put_uint(arg, bdev_io_min(bdev)); 545 case BLKIOOPT: 546 return put_uint(arg, bdev_io_opt(bdev)); 547 case BLKALIGNOFF: 548 return put_int(arg, bdev_alignment_offset(bdev)); 549 case BLKDISCARDZEROES: 550 return put_uint(arg, 0); 551 case BLKSECTGET: 552 max_sectors = min_t(unsigned int, USHRT_MAX, 553 queue_max_sectors(bdev_get_queue(bdev))); 554 return put_ushort(arg, max_sectors); 555 case BLKROTATIONAL: 556 return put_ushort(arg, !blk_queue_nonrot(bdev_get_queue(bdev))); 557 case BLKRASET: 558 case BLKFRASET: 559 if(!capable(CAP_SYS_ADMIN)) 560 return -EACCES; 561 bdev->bd_bdi->ra_pages = (arg * 512) / PAGE_SIZE; 562 return 0; 563 case BLKBSZSET: 564 return blkdev_bszset(bdev, mode, argp); 565 case BLKPG: 566 return blkpg_ioctl(bdev, argp); 567 case BLKRRPART: 568 return blkdev_reread_part(bdev); 569 case BLKGETSIZE: 570 size = i_size_read(bdev->bd_inode); 571 if ((size >> 9) > ~0UL) 572 return -EFBIG; 573 return put_ulong(arg, size >> 9); 574 case BLKGETSIZE64: 575 return put_u64(arg, i_size_read(bdev->bd_inode)); 576 case BLKTRACESTART: 577 case BLKTRACESTOP: 578 case BLKTRACESETUP: 579 case BLKTRACETEARDOWN: 580 return blk_trace_ioctl(bdev, cmd, argp); 581 case IOC_PR_REGISTER: 582 return blkdev_pr_register(bdev, argp); 583 case IOC_PR_RESERVE: 584 return blkdev_pr_reserve(bdev, argp); 585 case IOC_PR_RELEASE: 586 return blkdev_pr_release(bdev, argp); 587 case IOC_PR_PREEMPT: 588 return blkdev_pr_preempt(bdev, argp, false); 589 case IOC_PR_PREEMPT_ABORT: 590 return blkdev_pr_preempt(bdev, argp, true); 591 case IOC_PR_CLEAR: 592 return blkdev_pr_clear(bdev, argp); 593 default: 594 return __blkdev_driver_ioctl(bdev, mode, cmd, arg); 595 } 596 } 597 EXPORT_SYMBOL_GPL(blkdev_ioctl); 598